Lock cylinder assembly



Nov. 4, 1969 P. M. KoBREHEL 3,475,933 Y LOCK CYLINDER AS SEMBLY Filed March 29, 1968 l tlg. 'im l w iz y ZZ INVENTOR BY Pff@ zzz wel d@ 5 ff MM United States Patent Oice 3,475,933 Patented Nov. 4, 1969 U.S. Cl. 70-364 6 Claims ABSTRACT F THE DISCLOSURE A side bar lock cylinder includes an outer core rotatably mounted in a casing and rotatably mounting an inner core. Tumblers on the inner core normally block the side bar until arcuate, generally square-shaped slots in the tumblers are aligned with an arcuate ange on the first core.

This invention relates to lock cylinder assemblies and more particularly to side bar type lock cylinder assemblies.

One major object of this invention is to provide a side bar type lock cylinder assembly which requires a precisely bitted key for moving the side bar blocking tumblers to unblocking position to permit the side bar to move to unlocked position. Another major object is lto provide such an assembly which prevents removal of the key when the side bar is in unlocked position by locking the tumblers against movement with respect to the key. A further major object is to provide a side bar type lock cylinder assembly having a side bar for locking a core against rotation and a plurality of side bar blocking tumblers having generally square shaped openings which must be precisely aligned with an intertting similar shaped rib on the core by a properly bitted key before the tumblers can be moved to unblocking position.

These and other objects of this invention will be readily apparent from the following specification and drawings wherein:

FIGURE 1 is a plan view of a lock cylinder assembly according to this invention;

FIGURE 2 is an enlarged sectional view taken generally along the plane indicated by line 2 2 of FIGURE 1 and showing the assembly in locked position;

FIGURE 3 is a view similar to FIGURE 2 showing the assembly in partially unlocked position;

FIGURE 4 is a view similar to FIGURE 3 showing the assembly in fully unlocked position; and

FIGURE 5 is a view taken generally along the plane indicated by line 5-5 of FIGURE 2.

Referring now particularly to FIGURES l and 5 of the drawings, the assembly includes an outer casing structure 10, an outer or rst core 12 rotatably mounted within the casing structure 10, and an inner or second core 14 rotatably mounted within the core 12.

As best shown in FIGURE 5, the casing structure includes an annular shell-like body 16 having an annular flange 18 which is received within an annular bore 20 of a head 22 and secured thereto by staking a ange 24 of the head over the flange 18. The head 22 includes an axial opening 26 for the reception of a key as will be further described. The core 12 is rotatably mounted within the body 16 and an apertured annular flange 28 of the body limits inward movement of the core 12 within the body. The core 12 includes an annular outwardly extending coupling or operating portion 30 which extends through the ange 28 for connection to a ydevice to be operated.

The bore 32 of the core 12 is of varying cross sectional shape and the inner core 14 is rotatably mounted in this bore. The inner annular end 34 of the core 14 seats within an annular bore 36 of core 12 and an outer annular ange 38 of the core 14 seats within an annular bore 40 of the core 12 to rotatably support the inner and outer ends of the core 14 within the core 12. It will be understood, of course, that the cores 12 vand 14 are first assembled to each other and are then assembled to the body 16 before the body 16 is assembled to the head 22.

Core 12 includes a slot 42 which slidably supports a side bar 44. A pair of metal strips 46, FIGURE 5, are staked within axially inner and outer vertically enlarged openings 48 to slot 42 and coil compression springs 50 seat on these strips and also on extensions 52 of the side bar to continually bias the side bar inwardly of the core 12. Also, as shown in FIGURE 3, the outer end of the side bar is curved so as to lit flush against the like-curved base wall 54 of an opening in body 16 and is provided with a slightly raised lip 56 which is received within a likeshaped groove S8 in the upper side wall of the opening in body 16 should the core 12 be rotated relative to the body 16 without first moving the side bar 44 inwardly to its unlocked position, as will be described.

The inner core 14 is provided with a central ribbed slot 60 which receives the key inserted through opening 26 and is traversed by a number of generally T-shaped through slots 62, FIGURE 5. A tumbler 64 is slidably mounted in each slot 62 and each tumbler is bitted as selected. The tumblers are provided with ribs 66 which are slidably received within like-shaped portions of the slots 62 so that the tumblers cannot rotate within the slots. A coil compression spring 67 seats between a shoulder 68 of each tumbler and a metal strip 69 which is staked at its ends at 70 to the core 14 and covers the through bores 72 in the core 14 which open to slots 62 and house the springs 67. Springs 67 continually bias the tumblers 64 downwardly to their locked position shown in FIGURE 2 wherein the lower curved edges of the tumblers engage the like-shaped lower wall 73 of bore 32.

Each tumbler includes a blocking edge 74 which normally engages the inner edge of the side bar 44 to prevent any movement of the side bar inwardly of the core 12 when the tumblers are in locked position as shown in FIGURE 2. Each tumbler further includes an arcuate slot 76 which receives a like-shaped arcuate rib or ange 78 of the core 12 when the tumblers are in unlocked position as shown in FIGURE 4. A pair of coil compression springs 80 seat -on a flat metal strip 82 staked to the core 12 and also on a lateral llange 84 of the core 14 to continually bias the core 14 in a counterclockwise direction within the core 12 and hold the edges of the tumblers 64 in engagement with the side bar 44 and the wall 86 0f bore 32through which slot 42 opens.

When a properly bitted key is not inserted into the slot 60 through the opening 26, the lock cylinder is in locked position as shown in FIGURE 2. Springs 67 locate the tumblers as shown with their lower edges engaging wall 73 and their slots 76 out of alignment with llange 78 In this position, the blocking edges 74 of the tumblers engage the inner edge of the side bar 44 and wall 86 under the action of springs 80 to prevent any movement of the side bar inwardly of the core 12. Thus, cores 12 and 14 cannot rotate relative to the body 16, which of course is fixed to a support. Clockwise rotation of the core 14 within the core 12 is blocked by the engagement of the edges of the tumblers with the edge of the arcuate flange 78 of core 12.

When a properly bitted key 88 is inserted into the slot 60 through the opening 26, each of the tumblers 64 is raised from its FIGURE 2 position to its FIGURE 3 position to align the arcuate slots 76 with the arcuate ange 78. In this position of the tumblers, the tumblers still block any movement of the side bar 44 inwardly of the core 12. When the key is then rotated, the inner core 14 is rotated from its FIGURE 3 position to its position shown in FIGURE 4 wherein the flange 84 of the inner core engages a lateral shoulder 90 of the core 12 to block any further movement of the core 14 independently of the core 12. The slots 76 in the tumblers receive the flange 78 as the core 14 is rotated within the core 12. The turnblers 64 move with the core to unblocking position, as shown in FIGURE 4, to permit the springs 50 to withdraw the side bar 44 within the core 12 and thereby release the core 12 from the body 16 for rotation. Thereafter the cores 12 and 14 can be further rotated in a clockwise direction as a unit to operate whatever mechanism is to be operated.

When the tumblers 64 are interlocked with the flange 78, these tumblers are locked against any vertical or reciprocal movement relative to the core 14. By having one of the tumblers remote from the opening of the slot 60 engageable with a higher bitted shoulder of the key, any withdrawal of the key is prevented when the core 14 is in its position shown in FIGURE 4. This feature is useful if the subject lock cylinder assembly is used as part of an ignition switch for a vehicle.

It is believed evident that counterclockwise rotation of the core 14 within the core 12 returns the core 14 to its position shown in FIGURE 3 and thereafter subsequent withdrawal of the key permits the springs 67 to return the tumblers 64 to their locked position shown in FIG- URE 2.

Due to the shape of the slots 76 and the flange 78, the slots must be precisely aligned with the flange before any interfitting can take place. If there is any misalignment due to an improperly bitted key, even if one of the depths of the key is a half a bitting depth off, the flange 78 will engage the edge of a tumbler so that the cylinder assembly will remain in locked position. Likewise, such an arrangement provides for increased anti-pick protection since it is quite difficult for the picker to align all of the tumbler slots with the flange.

Thus this invention provides an improved lock cylinder assembly.

What is claimed is:

1. A lock cylinder assembly, comprising, in combination a casing structure, a first core rotatably mounted within the casing structure, a side bar mounted in the first core for movement between locked and unlocked positions with respect to the casing structure, a second core rotatably mounted in the first core, cooperating means on the first and second cores permitting limited rotational movement of the second core within the first core and requiring subsequent unitary rotational movement of the cores, a plurality of tumblers mounted in the second core for movement therewith and independent movement relative thereto, each tumbler including a side bar blocking portion blocking movement of the side bar to unlocked position in all independently movable positions of the tumblers, alignable interfitting means on the tumblers and first core misaligned in all but one independently movable position of each tumbler to block rotational movement of the tumblers to unblocking position and rotational movement of the second core within the first core, means on each tumbler engageable by a properly bitted key inserted within the second core to locate each tumbler in the one independently movable position and align the alignable inter-fitting means on the tumblers and first core, limited rotational movement of the second core within the first core interfitting the alignable means as the tumblers move to unblocking position to permit the side bar to move to unlocked position and permit subsequent unitary rotational movement of the cores.

2. The combination recited in claim 1 wherein the alignable means includes a slot in each tumbler having generally equally spaced arcuate edge portions generated about the axis of rotation of the second core, and a likeshaped flange on the first core aligned with the slots in the one independently movable position of each tumbler.

3. The combination recited in claim 2 wherein the slots open to an edge of each tumbler, with the edges of the tumblers being engageable with the flange to block rotational movement of the second core when the slots and flange are misaligned.

4. The combination recited in claim 1 wherein the cooperating means includes radial anges on the first and second cores normally located in circurnferentially spaced relationship by spring means extending therebetween, movement of the first core relative to the second core being resisted by the spring means.

5. The combination recited in claim 1 wherein the side bar is received within a slot in the casing structure and includes a lip at the free edge portion thereof receivable within a like-shaped groove in a Wall of the casing structure slot to interlock the side bar and casing structure upon forced rotation of the first core relative to the casing structure.

6. A lock cylinder assembly, comprising, in combination a casing structure having a side bar receiving slot, a first core rotatably mounted within the casing structure, a side bar slidably mounted in a slot in the first core for movement into and out of the casing structure slot to lock and unlock the first core and the casing structure, a second core rotatably mounted in a bore of the first core, cooperating means on the first and second cores permitting limited rotational movement of the second core within the first core and requiring subsequent unitary rotational movement of the cores, a plurality of tumblers mounted in the second core for unitary rotational movement therewith to unblocking position and independent movement relative thereto, each tumbler including an edge engageable with the side bar in all independently movable positions of the tumblers to block movement of the side bar out of the casing structure slot to unlocked position, alignable interfitting slot and flange means on the tumblers and first core misaligned in all but one independently movable position of each tumbler to block unitary rotational movement of the tumblers and second core within the first core, means on each tumbler engageable by a properly bitted key inserted within the second core to locate each tumbler in the one independently movable position and align the alignable slot and flange means on the tumblers and rst core, limited rotational movement of the second core within the first core interfitting the slot and flange means to move the tumblers to unblocking positions and permit movement of the side bar to unblocked position.

References Cited UNITED STATES PATENTS 2,648,972 8/1953 Spain 70-366 2,648,973 8/ 1953 Diesel 70-366 

